This invention relates to gas discharge display devices in general and more particularly, to a gas discharge display device with a gas discharge space which is separated, by a hole matrix with control electrodes arranged in rows and columns, from an electron acceleration space which is terminated by a picture screen.
One known gas discharge display device shown in FIG. 1 contains within an envelope 11 a matrix of gas discharge cells. Associated with the cells are auxiliary anodes 13 arranged in rows and control electrodes 15 arranged in columns. The gas discharge takes place in a gas discharge space 16 between a cathode 17 and the auxiliary anodes. The electrons are accelerated between the control electrodes 15 and the anode 19 in an electron acceleration space 21 by an applied high voltage. A hole matrix formed by a sheet 23 of insulating material divides the common discharge path into an auxiliary discharge space 16 of relatively great length for operation with low voltage for the gas discharge current, and a second space 21 of short path length and high field strength for accelerating the electrons. The hole matrix consisting of insulating material 23 is used as a carrier for the auxiliary anode associated with the rows of the matrix. The control electrodes, which are used for brightness control, are arranged on the opposite flat side of the matrix. The electrons, which are generated in the auxiliary glow discharge with a row by row control and are moved toward the auxiliary anode, are controlled point by point in the subsequent discharge path of high field strength by the accordingly divided control electrode 15, are accelerated and imaged on a phospherous screen 25.
The energy of an electron in the glow discharge is between a few electron volts (eV) and the full operating voltage of the discharge, which in general is several hundred eV. The brightness is controlled by applying a negative voltage to the control electrode. All electrons with an energy higher than the control voltage can enter the high voltage space unimpeded and are accelerated there. The number of fast electrons becomes smaller, the fewer number of collisions taking place between electrons and gas molecules. Therefore, the distance between the auxiliary anodes and the negative glow, the kind of filling gas used and the gas pressure are the most important parameters which influence the energy distribution of the electrons. The number of collisions can be increased by adjusting the distance between the auxiliary anodes and the negative glow; the effectiveness of the collisions, however, depends essentially on the collision cross sections of the gas.